A hip joint femoral prosthesis

Abstract

This invention discloses a femoral prosthesis for the hip joint, belonging to the field of medical device technology. The femoral prosthesis includes a femoral stem and a femoral head movably connected to the femoral stem. The femoral stem includes a rigid stem neck and a flexible stem body. The rigid stem neck and the flexible stem body are detachably connected. One end of the rigid stem neck is movably connected to the femoral head, and the other end is connected to the flexible stem body. By dividing the femoral stem structure into a rigid stem neck and a flexible stem body, and adopting a detachable connection method, the femoral stem forms a longitudinal mechanical partition structure. This reduces the overall stiffness of the stem body while ensuring the strength of the neck, improving the load transfer mode, and reducing stress shielding effects.

Description

Technical Field

[0001] This invention relates to the field of medical device technology, and more particularly to a hip joint femoral prosthesis. Background Technology

[0002] Total hip arthroplasty is an important treatment for femoral neck fractures, avascular necrosis of the femoral head, and degenerative hip joint diseases. The femoral component, as a crucial part of the artificial hip joint, typically consists of the femoral head and the femoral stem.

[0003] In existing technologies, the femoral head is mostly made of cobalt-chromium-molybdenum alloy or ceramic materials, while the femoral stem is mostly made of titanium alloy. The femoral head and stem are typically connected using a Morse taper joint structure. However, existing femoral components still have defects during long-term clinical use. For example, under repeated loading, the inner cone of the femoral head and the outer cone of the femoral stem are prone to micromovements, leading to frictional corrosion or crevice corrosion at the interface, resulting in the release of metal ions, which may cause local soft tissue reactions or even prosthesis loosening. Furthermore, the elastic modulus of human cortical bone is approximately 2.2–23.4 GPa, while the elastic modulus of commonly used titanium alloys is approximately 110 GPa, a significant difference. After implantation, the load is mainly borne by the high-rigidity proximal femoral bone, leading to reduced stress in the proximal femoral bone tissue, creating a stress shielding effect, and subsequently causing bone resorption.

[0004] Therefore, how to reduce the overall elastic modulus of the femoral stem while ensuring its mechanical strength and structural stability, thereby improving its mechanical matching relationship with natural bone tissue, is a technical problem that urgently needs to be solved in this field. Summary of the Invention

[0005] The purpose of this invention is to provide a hip joint femoral prosthesis that addresses the problem of how to reduce the overall elastic modulus of the femoral stem while ensuring its mechanical strength and structural stability, thereby improving its mechanical compatibility with natural bone tissue.

[0006] To achieve this objective, the present invention adopts the following technical solution: A hip joint femoral prosthesis includes a femoral stem and a femoral head movably connected to the femoral stem. The femoral stem includes a rigid stem neck and a flexible stem body. The rigid stem neck is detachably connected to the flexible stem body. One end of the rigid stem neck is movably connected to the femoral head, and the other end is connected to the flexible stem body.

[0007] Optionally, the rigid handle neck is made of titanium alloy, and the flexible handle body is made of carbon fiber reinforced polyetheretherketone material, wherein the carbon fiber content in the carbon fiber reinforced polyetheretherketone in the flexible handle body is 25%-35%.

[0008] Optionally, the femoral head is made of pure polyarylether materials.

[0009] Optionally, the rigid stem neck is composed of an integrally formed mounting section and a plug-in section, the femoral head is connected to the plug-in section, the side of the mounting section opposite to the plug-in end is a first mounting surface, the upper end surface of the flexible stem body is a second mounting surface, and the first mounting surface and the second mounting surface fit together and have the same outline.

[0010] Optionally, the angle between the axis of the insertion segment and the axis of the flexible handle body is the neck-shaft angle, the length of the insertion segment is the neck length, and the vertical height of the insertion segment is the neck height. The installation position of the femoral head is determined by the neck-shaft angle, neck length, and neck height. The rigid shank neck is a replaceable structural component with a preset optimal neck length, neck height, and neck angle.

[0011] Optionally, the flexible handle body has an embedding groove on the proximal side near the rigid handle neck, and a protrusion is provided on the first mounting surface of the rigid handle neck. When the first mounting surface and the second mounting surface are in contact, the protrusion is embedded in the embedding groove.

[0012] Optionally, the rigid neck of the handle has a through hole that passes through the protrusion, and the bottom of the groove of the embedded groove has a threaded groove coaxially arranged with the through hole. The rigid neck of the handle and the flexible body are detachably connected by bolts.

[0013] Optionally, a biomimetic trabecular structure is formed on the sidewall of the proximal end of the flexible handle.

[0014] Optionally, the flexible handle body surface is coated with a pure titanium and hydroxyapatite coating.

[0015] This invention also provides a method for preparing a hip joint femoral prosthesis as described above, comprising the following steps: A rigid shank neck is formed using titanium alloy material; The flexible handle body is formed by injection molding carbon fiber reinforced polyetheretherketone material. A biomimetic trabecular structure is formed on the flexible handle body by compression molding or 3D printing. A pure titanium coating and a hydroxyapatite coating are formed on the surface of the flexible handle. The neck is press-fitted to the stem, and the femoral head is installed on the neck to form a femoral component prosthesis.

[0016] Compared with the prior art, the present invention has the following beneficial effects: In the femoral prosthesis of the hip joint provided in this invention, the rigid stem neck has high overall structural rigidity to ensure that it does not undergo excessive deformation under long-term human load. The flexible stem body has a certain elastic deformation capacity, allowing it to produce controlled micro-deformation under axial and bending loads, thereby effectively reducing proximal stress concentration and improving the force transmission path. The rigid stem neck and flexible stem body can be detachably connected by press-fitting, bolting, or other methods, forming a split structure. This allows for the replacement of stem necks of different specifications according to clinical needs, improving the applicability of the femoral stem prosthesis. By dividing the femoral stem structure into a rigid stem neck and a flexible stem body and adopting a detachable connection method, the femoral stem forms a longitudinal mechanical partition structure, thereby reducing the overall rigidity of the stem body while ensuring the strength of the neck, improving the load transmission method, and reducing stress shielding effects. Attached Figure Description

[0017] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0018] The structures, proportions, sizes, etc., shown in the accompanying drawings of this specification are only for the purpose of assisting those skilled in the art in understanding and reading the content disclosed in the specification, and are not intended to limit the conditions under which the present invention can be implemented. Therefore, they have no substantial technical significance. Any modifications to the structure, changes in the proportions, or adjustments to the size, without affecting the effects and objectives that the present invention can produce, should still fall within the scope of the technical content disclosed in the present invention.

[0019] Figure 1 This is a schematic diagram of the structure of a hip joint femoral prosthesis.

[0020] Figure 2 This is a front view of the femoral stem.

[0021] Figure 3 This is an exploded view of the structure of a hip joint femoral prosthesis.

[0022] Figure 4 This is a structural cross-sectional view of a hip joint femoral prosthesis.

[0023] Illustrations: 1. Femoral stem; 11. Rigid stem neck; 111. Perforation; 112. Protrusion; 12. Flexible stem body; 121. Insertion groove; 122. Threaded groove; 123. Bionic trabecular bone structure; 2. Femoral head. Detailed Implementation

[0024] To make the objectives, features, and advantages of this invention more apparent and understandable, the technical solutions of the embodiments of this invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the embodiments described below are only some embodiments of this invention, and not all embodiments. Based on the embodiments of this invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this invention.

[0025] In the description of this invention, it should be understood that the terms "upper," "lower," "top," "bottom," "inner," and "outer," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, and are only for the convenience of describing the invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of the invention. It should be noted that when a component is considered to be "connected" to another component, it can be directly connected to the other component or there may be a component positioned centrally in the connection.

[0026] The technical solution of the present invention will be further described below with reference to the accompanying drawings and specific embodiments.

[0027] Example 1: like Figures 1-4 As shown, this embodiment of the invention provides a femoral prosthesis for use in total hip replacement. Addressing the shortcomings of existing femoral prostheses, which suffer from low mechanical compatibility between the prosthesis and natural bone tissue due to structural and material factors, this embodiment of the invention aims to provide a femoral prosthesis that, through structural improvements, can better improve the mechanical compatibility between the prosthesis and natural bone tissue while ensuring the mechanical strength and structural stability of the femoral prosthesis.

[0028] like Figure 1 and Figure 3 As shown, in this embodiment, the femoral prosthesis includes a femoral stem 1 and a femoral head 2 movably connected to the femoral stem 1. The femoral stem 1 includes a rigid stem neck 11 and a flexible stem body 12. The rigid stem neck 11 and the flexible stem body 12 are detachably connected. One end of the rigid stem neck 11 is movably connected to the femoral head 2, and the other end is connected to the flexible stem body 12.

[0029] Specifically, the femoral head 2 has a spherical structure, and the rigid stem neck 11 has a tapered cylindrical connecting end for insertion and connection with the femoral head 2. Since the neck region connecting the femoral prosthesis to the femoral head 2 is a stress concentration area, it experiences significant bending moments and shear forces. Therefore, the rigid stem neck 11 has high overall structural rigidity to ensure no excessive deformation under long-term human load. The flexible stem body 12 is located at the distal end of the femoral stem 1 and implanted into the femoral medullary cavity. Its shape can be tapered or anatomical to adapt to the femoral cavity morphology. Furthermore, unlike the traditional integral rigid femoral stem 1, the stem body of the femoral stem 1 in this embodiment has a certain elastic deformation capacity, allowing it to undergo controlled micro-deformation under axial and bending loads, thereby effectively reducing proximal stress concentration and improving the force transmission path.

[0030] Meanwhile, the rigid stem neck 11 and the flexible stem body 12 can be detachably connected by means of press fitting, bolt connection, etc., so that the rigid stem neck 11 and the flexible stem body 12 form a split structure, thereby allowing the stem neck of different specifications to be replaced according to clinical needs, improving the applicability of the femoral stem 1 prosthesis.

[0031] By dividing the femoral stem 1 structure into a rigid stem neck 11 and a flexible stem body 12 and adopting a detachable connection method, the femoral stem 1 forms a longitudinal mechanical partition structure, thereby reducing the overall stiffness of the stem body while ensuring the strength of the neck, improving the load transmission mode, and reducing the stress shielding effect.

[0032] Furthermore, the rigid neck 11 is made of titanium alloy, and the flexible body 12 is made of carbon fiber reinforced polyetheretherketone material, and the carbon fiber content in the carbon fiber reinforced polyetheretherketone in the flexible body 12 is 25%-35%.

[0033] For example, the rigid neck 11 is integrally machined from medical-grade titanium alloy, preferably Ti-6Al-4V or Ti-6Al-7Nb medical-grade titanium alloy. After forging, it undergoes CNC precision machining to obtain its final shape. After machining, solution aging treatment and surface sandblasting or micro-arc oxidation can be performed to improve fatigue strength and surface wear resistance. The connection end between the neck and the femoral head 2 can be machined into a standard tapered fit structure to ensure the stability of the movable connection and the accuracy of repeated assembly.

[0034] The flexible handle body 12 is made of carbon fiber reinforced polyetheretherketone material, wherein the carbon fiber content is 25% to 35%, preferably 30%; wherein the carbon fiber can be continuous carbon fiber or chopped carbon fiber, preferably chopped carbon fiber with a length of 3mm to 8mm, so as to facilitate uniform dispersion during the injection molding process, and the flexible handle body 12 is prepared by injection molding process.

[0035] Understandably, by controlling the orientation of carbon fibers to increase their longitudinal distribution along the handle, axial load-bearing capacity can be enhanced, while maintaining a certain degree of flexibility in the transverse direction. This allows the elastic modulus of the flexible handle portion 12 to be controlled within the range of 10GPa to 20GPa, which is closer to the elastic modulus range of human cortical bone, thus significantly reducing overall stiffness. Furthermore, through optimization of material proportions and process parameters, the bending strength of the handle can reach over 150MPa, and its fatigue life can meet the requirements of millions of cycles of human walking load.

[0036] By separating the rigid stem neck 11 and the flexible stem body 12, and differentiating their strengths, the rigid titanium alloy stem neck 11 ensures high strength and bending resistance in the femoral head 2 connection area, while the carbon fiber reinforced polyetheretherketone (PEEK) stem body reduces overall bending stiffness, allowing the load to be gradually transferred to the bone tissue, thereby reducing stress shielding effects and lowering the risk of proximal femoral bone resorption. Simultaneously, the separate structural design also reduces interfacial shear stress, improving long-term biological fixation stability; and due to the excellent corrosion resistance of the materials themselves, it also reduces the risk of metal ion release, improving biocompatibility.

[0037] Furthermore, the femoral head 2 is made of pure polyarylether materials.

[0038] For example, the polyarylether material is preferably polyetheretherketone (PEEK) or polyetherketoneketone (PEKK). The material purity preferably meets medical-grade standards, without the addition of metal fillers or inorganic reinforcing particles, to ensure overall material uniformity and interfacial stability. Its crystallinity is preferably controlled between 30% and 40% to ensure both wear resistance and impact resistance. The inner side of the femoral head 2 can be machined to form a conical cavity or limiting cavity that matches the rigid stem neck 11, ensuring a reliable movable connection during assembly. The inner cavity surface can be plasma-treated or micro-roughened to improve fit stability.

[0039] It should be noted that, due to the excellent wear resistance and impact resistance of polyarylether materials, they can maintain stable mechanical properties even after long-term immersion in physiological saline environment. Their density is significantly lower than that of metallic materials, thus reducing the overall weight of the prosthesis. The elastic modulus of this material is approximately 3 GPa to 4 GPa, which is closer to biological tissue than that of traditional metallic femoral heads2, and can absorb impact loads to a certain extent, reducing the peak instantaneous stress.

[0040] Furthermore, pure polyarylether materials do not contain metal elements, and will not produce metal ion precipitation problems during long-term use, thus reducing the risk of adverse tissue reactions caused by metal wear. At the same time, their low coefficient of friction allows them to maintain stable tribological properties when used with polymeric acetabular liners.

[0041] The femoral head 2, made of pure polyarylether materials, can effectively reduce weight, improve stability and biocompatibility while ensuring sufficient mechanical strength. Furthermore, by using it in conjunction with the split femoral stem 1, which consists of a rigid stem neck 11 and a flexible stem body 12, the overall mechanical transmission path can be further optimized, thereby improving the long-term stability of the prosthesis.

[0042] like Figure 2 , Figure 3 and Figure 4 As shown, in this embodiment of the invention, the rigid stem neck 11 is composed of an integrally formed mounting section and a plug-in section. The femoral head 2 is connected to the plug-in section. The side of the mounting section opposite to the plug-in end is the first mounting surface, and the upper end surface of the flexible stem body 12 is the second mounting surface. The first mounting surface and the second mounting surface fit together and have the same outline.

[0043] Specifically, the rigid stem neck 11 is a one-piece molded structure. The mounting section is used to connect and mate with the flexible stem body 12, and the insertion section is used to connect the femoral head 2. The first mounting surface of the mounting section and the second mounting surface of the flexible stem body 12 are completely fitted and have the same contour. At the same time, both the first and second mounting surfaces are bent surfaces composed of two planes, so that the rigid stem neck 11 and the flexible stem body 12 form an anti-rotation limiting structure, ensuring that the femoral stem 1 maintains stable mechanical contact, avoiding micromovement and loosening problems, and improving the long-term stability of the prosthesis.

[0044] Furthermore, the angle between the axis of the insertion segment and the axis of the flexible stem body 12 is the neck-shaft angle, the length of the insertion segment is the neck length, and the vertical height of the insertion segment is the neck height. The installation position of the femoral head 2 is determined by the neck-shaft angle, neck length, and neck height. Among them, the rigid stem neck 11 is a replaceable structural component, used to match the optimal neck length, neck height, and neck-shaft angle according to the patient.

[0045] Specifically, the insertion segment is a columnar structure. The rigid stem neck 11 and the flexible stem body 12 form an obtuse angle α along their length, which is called the neck-shaft angle. After the femoral head 2 is assembled into the insertion segment, the distance b from the center of the femoral head 2 to the bottom of the insertion segment is the neck length of the rigid stem neck 11, and the vertical distance c from the center of the femoral head 2 to the bottom of the insertion segment is the neck height of the rigid stem neck 11. The neck-shaft angle, neck length, and neck height together determine the position of the center of the femoral head 2, thereby determining the installation position of the femoral head 2. According to the design requirements of the femoral stem 1, the neck-shaft angle is usually between 120° and 135° to accommodate the femoral anatomy of different patients. However, the dimensions of the femoral anatomy vary among different patients. If the size of the femoral prosthesis does not match the dimensions of the patient's femoral anatomy, it will affect the flexion-extension angle, abduction angle, and corresponding mechanical fit of the hip joint. Therefore, by precisely controlling the neck-shaft angle a, neck length a, and neck height c of the rigid stem neck 11, the installation position of the femoral head 2 can be precisely adjusted. In order to achieve personalized matching for different patients, the rigid stem neck 11 is designed as a replaceable structural component. Patients can choose different specifications of neck length, neck height, and neck-shaft angle according to their own anatomical requirements, thereby improving the matching degree and adaptability of the femoral prosthesis.

[0046] In this embodiment of the invention, the flexible handle body 12 is provided with an embedding groove 121 on the proximal side near the rigid handle neck 11, and a protrusion 112 is provided on the first mounting surface of the rigid handle neck 11. When the first mounting surface and the second mounting surface are in contact, the protrusion 112 is embedded in the embedding groove 121.

[0047] Specifically, the insert groove 121 can be located at the second mounting surface of the flexible handle body 12. The cross-sectional shape of the insert groove 121 can be rectangular or polygonal, providing anti-rotation effect to improve the torsional resistance after connection. A protrusion 112 is correspondingly provided on the first mounting surface of the rigid handle neck 11. The shape of the protrusion 112 matches that of the insert groove 121 to form a positioning and fitting structure. The protrusion 112 can be integrally formed with the rigid handle neck 11. When the first mounting surface and the second mounting surface are in contact, the protrusion 112 is embedded in the insert groove 121, forming an axial insertion limiting structure. At the same time, a snap-fit ​​assembly structure can be provided between the protrusion 112 and the insert groove 121 to achieve a fixed connection between the rigid handle neck 11 and the flexible handle body 12. This effectively prevents relative rotation or shear slippage between the rigid handle neck 11 and the flexible handle body 12.

[0048] Furthermore, the rigid neck 11 has a through hole 111 through the protrusion 112, and the bottom of the groove 121 has a threaded groove 122 coaxially arranged with the through hole 111. The rigid neck 11 and the flexible body 12 are detachably connected by bolts.

[0049] For example, after the rigid neck 11 and the flexible body 12 are assembled, the through hole 111 and the threaded groove 122 are coaxial and connected. A bolt is passed through the through hole 111 and screwed into the threaded groove 122, thereby achieving a fixed connection between the rigid neck 11 and the flexible body 12. The bolt can also be made of titanium alloy to ensure a stable connection between the rigid neck 11 and the flexible body 12; alternatively, the bolt can be made of pure polyarylether material, which can effectively prevent fretting corrosion while ensuring the stability between the rigid neck 11 and the flexible body 12.

[0050] For example, a biomimetic trabecular structure 123 is formed on the sidewall of the proximal end of the flexible stem portion 12. The flexible stem portion 12 is formed by injection molding, and the biomimetic trabecular structure 123 can be formed during injection molding, or it can be formed by 3D printing. The biomimetic trabecular structure 123 is located in the area where the femoral stem 1 prosthesis contacts the proximal cancellous bone of the femur after implantation, preferably distributed in the proximal 1 / 3 to 1 / 2 length of the stem portion. The biomimetic trabecular structure 123 can be a porous mesh structure, and its overall shape simulates the arrangement of trabeculae in human cancellous bone. The three-dimensional interconnected channels of the biomimetic trabecular structure 123 can promote bone tissue growth into the prosthesis, achieving mechanical interlocking biological fixation. After implantation, the newly formed bone tissue can form a bone bridge structure within the pores, improving the initial and long-term stability of the prosthesis.

[0051] Furthermore, the flexible handle portion 12 is coated with a pure titanium and hydroxyapatite coating. The pure titanium coating can be formed using plasma spraying or cold spraying processes, and its thickness is preferably 50 μm to 300 μm, used to improve surface roughness and initial mechanical bonding. The pure titanium layer improves the interfacial compatibility between the flexible substrate and bone tissue, while providing a good transition layer to enhance the adhesion of the subsequent hydroxyapatite coating.

[0052] The biomimetic trabecular bone structure 123 provides a physical interlocking basis, the pure titanium coating enhances the interface roughness and initial stability, and the hydroxyapatite coating promotes rapid bone tissue growth and mineralization deposition, thereby significantly shortening the bone integration time, improving the initial stability of implantation, and enhancing the long-term fixation reliability.

[0053] Example 2: This invention also provides a method for preparing the above-mentioned hip joint femoral prosthesis, comprising the following steps: Step S1: A rigid shank neck 11 is formed by processing titanium alloy material; For example, the processing of titanium alloys may include forging, solution aging heat treatment, and CNC precision machining. Forging improves the material's density and fatigue properties, followed by solution aging to achieve stable mechanical properties. CNC machining is used to form the plug section, mounting section, and structural features such as protrusions 112 and perforations 111. After machining, surface sandblasting or micro-arc oxidation treatment can be performed to improve surface wear resistance and fatigue resistance.

[0054] Step S2: The flexible handle body 12 is formed by injection molding of carbon fiber reinforced polyetheretherketone material; For example, carbon fiber reinforced polyetheretherketone (PEEK) materials can be prepared by twin-screw extrusion blending, with the extrusion temperature controlled between 360°C and 390°C to ensure uniform dispersion of carbon fibers in the matrix. After obtaining granules, injection molding is performed, preferably at around 380°C, with the mold temperature controlled between 180°C and 200°C to improve the material's crystallinity and mechanical properties. Following molding, annealing is carried out, preferably at 200°C to 250°C, for 2 to 4 hours to eliminate internal stress and improve dimensional stability.

[0055] Step S3: Form a biomimetic trabecular structure 123 on the flexible handle body 12 by molding or 3D printing. Step S4: Form a pure titanium coating and a hydroxyapatite coating on the surface of the flexible handle 12; The pure titanium coating can be formed using plasma spraying or cold spraying processes, with a thickness controlled between 50 μm and 300 μm, to improve interface roughness and initial mechanical stability. Subsequently, a hydroxyapatite coating, preferably 30 μm to 150 μm thick, is sprayed onto the pure titanium layer surface. After spraying, a low-temperature heat treatment can be performed to improve the coating's bonding strength and stability.

[0056] Step S5: Press-fit the neck to the stem and install the femoral head 2 on the neck to form a femoral component prosthesis.

[0057] The embodiments of the present invention, through a systematic manufacturing process from material selection and structural construction to surface bioactivation, enable the resulting femoral prosthesis to possess mechanical compatibility, biointegration capability, and long-term stability, significantly improving the stress shielding and long-term loosening problems of traditional integral metal femoral stems, and enhancing the safety and durability of clinical use.

[0058] The above-described embodiments are only used to illustrate the technical solutions of the present invention, and are not intended to limit it. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A hip joint femoral prosthesis, characterized in that, It includes a femoral stem (1) and a femoral head (2) movably connected to the femoral stem (1). The femoral stem (1) includes a rigid stem neck (11) and a flexible stem body (12). The rigid stem neck (11) and the flexible stem body (12) are detachably connected. One end of the rigid stem neck (11) is movably connected to the femoral head (2), and the other end is connected to the flexible stem body (12).

2. The hip joint femoral prosthesis according to claim 1, characterized in that, The rigid neck (11) is made of titanium alloy, and the flexible body (12) is made of carbon fiber reinforced polyether ether ketone material. The carbon fiber content in the carbon fiber reinforced polyether ether ketone in the flexible body (12) is 25%-35%.

3. The hip joint femoral prosthesis according to claim 1, characterized in that, The femoral head (2) is made of pure polyarylether materials.

4. The hip joint femoral prosthesis according to claim 1, characterized in that, The rigid stem neck (11) is composed of an integrally formed mounting section and a plug-in section. The femoral head (2) is connected to the plug-in section. The side of the mounting section opposite to the plug-in end is the first mounting surface. The upper end surface of the flexible stem body (12) is the second mounting surface. The first mounting surface and the second mounting surface fit together and have the same outline.

5. The hip joint femoral prosthesis according to claim 4, characterized in that, The angle between the axis of the insertion segment and the axis of the flexible handle (12) is the neck-shaft angle, the length of the insertion segment is the neck length, and the vertical height of the insertion segment is the neck height. The installation position of the femoral head (2) is determined by the neck-shaft angle, neck length, and neck height. The rigid shank neck (11) is a replaceable structural component with a preset optimal neck length, neck height, and neck angle.

6. The hip joint femoral prosthesis according to claim 5, characterized in that, The flexible handle body (12) has an inlay groove (121) on the proximal side near the rigid handle neck (11). A protrusion (112) is provided on the first mounting surface of the rigid handle neck (11). When the first mounting surface and the second mounting surface are in contact, the protrusion (112) is embedded in the inlay groove (121).

7. The hip joint femoral prosthesis according to claim 6, characterized in that, The rigid neck (11) has a through hole (111) that passes through the protrusion (112), and the bottom of the groove (121) has a threaded groove (122) that is coaxial with the through hole (111). The rigid neck (11) and the flexible body (12) are detachably connected by bolts.

8. The hip joint femoral prosthesis according to claim 2, characterized in that, A biomimetic trabecular structure (123) is formed on the side wall of the proximal end of the flexible handle (12).

9. The hip joint femoral prosthesis according to claim 1, characterized in that, The flexible handle (12) is coated with a pure titanium and hydroxyapatite coating.

10. A method for preparing a hip joint femoral prosthesis as described in any one of claims 1-9, characterized in that, Includes the following steps: A rigid shank neck is formed by processing titanium alloy material (11); The flexible handle body is formed by injection molding of carbon fiber reinforced polyetheretherketone material (12); A biomimetic trabecular structure (123) is formed on the flexible handle (12) by compression molding or 3D printing. A pure titanium coating and a hydroxyapatite coating are formed on the surface of the flexible handle (12); The neck is press-fitted to the stem, and the femoral head (2) is installed on the neck to form a femoral component prosthesis.

Images